[php-src] Issue #19153: Attribute validation should error on trait/interface/enum/abstract class

Issue: https://github.com/php/php-src/issues/19153 Author: DanielEScherzer ### Description See https://3v4l.org/99PhY ```php <?php #[Attribute] enum DemoEnum {} #[Attribute] trait DemoTrait {} #[Attribute] abstract class DemoAbstract {} #[Attribute] interface DemoInterface {} #[DemoEnum] #[DemoTrait] #[DemoAbstract] #[DemoInterface] function usesWrongAttrib() {} $r = new ReflectionFunction( 'usesWrongAttrib' ); $a = $r->getAttributes(); var_dump( $a ); foreach ( $a as $attrib ) { try { $attrib->newInstance(); } catch ( Error $e ) { echo get_class( $e ) . ": " . $e->getMessage() . "\n"; } } ``` currently outputs ``` array(4) { [0]=> object(ReflectionAttribute)#2 (1) { ["name"]=> string(8) "DemoEnum" } [1]=> object(ReflectionAttribute)#3 (1) { ["name"]=> string(9) "DemoTrait" } [2]=> object(ReflectionAttribute)#4 (1) { ["name"]=> string(12) "DemoAbstract" } [3]=> object(ReflectionAttribute)#5 (1) { ["name"]=> string(13) "DemoInterface" } } Error: Cannot instantiate enum DemoEnum Error: Cannot instantiate trait DemoTrait Error: Cannot instantiate abstract class DemoAbstract Error: Cannot instantiate interface DemoInterface ``` But we should have compile-time errors instead.